The subject of the present invention is a method and an apparatus for storing samples for the purpose of later analysing such samples to estabish the presence of fecal occult blood.
The analysis of excrement, whether it be performed in open (non-hospital) conditions or under hospital conditions has been inconvenient, from the practical point of view, for the persons taking the samples. Such samples are also difficult to pack for possible transportation (mail transport or messenger service), and are inconvenient to handle in the laboratory during examination of the sample. Also tests to establish fecal occult blood have also been methodologically laborious, and the range of (blood quantity to excrement mass) has often been either too high or too low.
All the tests used to establish hemorrhages occuring within the area of the intestinal canal are based on the transformation of hemin into hematin in the presence of hydrogen peroxide. In this connection, certain organic compounds are oxidizable into coloured compounds. All the methods of establishing fecal occult blood currently in use involve a great number of difficulties both in respect of the taking, storage, and transportation of the fecal samples and in respect of the establishment of the existence of fecal occult blood. The range of use of such tests is limited. These prior art tests are described below.
In the Weber Test, a pea-sized clod of excrement is taken; the excrement is then emulsified by means of glacial acetic acid-ether, and the existence of the blood is established in a test tube by the guaiacol-hydrogen-peroxide test. A positive sample yields a blue or violet colour. In this test, excrement balls have to be transported. This method is too insensitive and, for this reason it is about to be phased out of use.
The Wagner test, which uses benzidine has been phased out of use because of its excessive sensitivity. Benzidine is, moreover, a carcinogenic substance.
In the Orthotoluidine test, a clod of excrement is homogenized in a test tube. The excrement suspension is then boiled for 5 minutes, and then cooled down to the room temperature. A colour reaction is then performed on a china plate. Orthotoluidine is also a carcinogenic substance.
In the Hematest.sup.R (Ames) tablet test excrement is spread onto a filter paper and, the Hematest reagent is placed onto the applied excrement layer. A few drops of water are then dropped onto the tablet. In a positive test a blue intermediate ring is produced around the reagent.
In the Hemoccult.sup.R (Smith-Kline & French Laboratories) filter paper test excrement is spread onto a paper treated with guaiac resin. The resulting cardboard package is then sealed and sent to the laboratory, where one side of the carboard box is opened and hydrogen peroxide is dropped onto the rear side of the filter paper. A blue colour ring results for a positive sample. The quantity of excrement to be placed into the carboard box cannot be regulated in this arrangement, and excrement may be extruded through the open sides of the box.
In the apparatus and method in accordance with the present invention, the above difficulties are circumvented and it is possible to perform tests, such as, bacteria cultures on the fecal sample prepared in accordance with this method and apparatus. The characteristics of the invention are described more fully below.